Christian Pulisic fired the United States into the last 16 of the World Cup with a 1-0 win over Iran at Al Thumama Stadium in Qatar.The Chelsea striker grabbed the only goal of the game in the 38th minute when he bravely stole in to convert a headed cross by Sergino Dest from point-blank range.Iran summoned little in search of the equaliser that would have sent them through to a second-round clash with the Netherlands, with only a late diving header from Morteza Pouraliganji and a last-gasp VAR check causing American hearts to flutter.The US dominated the opening period to such an extent that the only fear was whether they would live to regret a catalogue of missed chances as they once again lacked cutting edge in the final third.Half-time Iran